Collecting Seeds

There is nothing more rewarding than growing a beautiful flower garden to enjoy each year, but buying annuals every season can be expensive. An easy way to ensure you have new plants each year is by collecting their seeds. So, let’s dig in and learn when and how to harvest seeds for next season.

Locating The Seeds

The first thing you will need to do is research how your plants put on seeds. Some plants carry seeds in the flower head, while others grow seed pods or produce flowering spikes.

Bluebonnets, Alliums, Mimosas, Poppies, and Nigella are all examples of flowers that grow a seed pod.

Zinnias, Marigolds, and Bachelor Buttons produce seeds from their flower heads.

Many herbs like Oregano, Dill, and Basil grow a flower spike that produces seeds.

When To Collect Seeds

The most important step to collecting seeds is to recognize when to gather them. If you pick immature seeds they won’t germinate when planted. A good rule of thumb is to let the flowers die back and dry before collecting their seeds.

Here’s an example of an immature Bluebonnet seed pod. Notice how green it still is.

Here’s a Bluebonnet seed pod that has matured and seeds are ready to be gathered. The pods are dry and many have split open to disperse the seeds.

For many pod-producing plants, the ‘rattle’ test can tell you if the seeds are mature yet. Give the pod a shake and listen for the seeds to rattle inside. Poppies and Larkspurs are great candidates for this.

The same basic principle applies to flowering seed heads. If the flower is vibrant and colorful, the seeds are immature. Dried, ‘dead’ looking flowers are a good indication that the seeds are ready to be harvested.

Here’s an example of a Zinnia with a mature seed head:

Plants that put on ‘spikes’ follow the same principle. Towards the end of their season, herbs like Basil will grow a flower spike. These flowers will eventually dry and mature into Basil seeds.

How To Collect Flower Seeds

How you collect seeds will vary depending on the type of flower or herb you are growing.

For plants that produce pods, like Larkspurs or Poppies, I will generally cut the pod off the plant and place them in a zip-top bag or closed container. Once I’ve gathered them up, I’ll simply give it a good shake to release all the seeds. You can pull the empty seed pods out if you like, but it isn’t necessary.

To collect seeds from flowering heads, simply pull the dried petals off the flower. Generally, the seed is at the base of the petal. Here’s an example of Bachelor Button seeds. On the bottom right you can see the dried flower head where the petals have set seed. Simply pulling the ends out of the head will expose the flower seeds.

Plants that produce seed spikes are also very easy to collect. Simply run your fingers along the spike to release and collect the seeds.

Storing Collected Seeds

Once you have collected seeds for next season, it’s time to store them. Properly stored seeds can last a few years, but their viability will start to diminish. I generally will only keep mine two years before discarding them.

Moisture is detrimental to seeds, as it can encourage rot and fungal growth. Therefore, it’s imperative that your seeds are completely dry before you store them. I will often spread mine out on a tray for a day or two before storing.

Good air flow is also critical to preserving seeds. Paper is the best material to store your seeds in. Plastic bags are a ‘no-no’, as they trap moisture. Envelopes are a great option, or you can buy empty seed packets inexpensively. Silica desiccant packets are also useful in keeping your seeds dry. I save them from shoe boxes to add into my envelopes for extra protection.

Collecting Seeds: Enjoying The Harvest

It’s so rewarding to collect and save your own seeds! Your hard work now will ensure plenty of beautiful flowers next year, and that’s definitely motivation for me to get picking. Until then, Happy Growing!